If your scene is mostly white (white paper background) then that will trick the light meter in your camera...so yes, you would need to add positive exposure.

To simplify things, I would put the camera into manual mode and take test shots. Look at the histogram after each shot and adjust the exposure until most of the graph is close to the right side.

That should help, but it's still possible that your subject will be brighter than you want, and the background might not be all the way white. So like I said before, you may need to put more light onto the background (without putting more light onto the subject.)